Needle-bar-guiding mechanism for sewing-machines.



No. 698,484. Y 1 Patented Apr. 29, |902.

W. FORSYTH. NEEDLE BAR GUIDINGAMECHA'NISM FOR SEWING MACHINES.

(Application ld Nov. 8, 1901.)

(No Model.)

UNITED STATES PATENT FFICE.

W'ILLIAM FORSYTH, 0F BELVIDERE, ILLINOIS.

NEEDLE-BAR-GUIDING MEC'HANISM FOR SEWING-MACHINES.

i SEECIFICATIQN forming part of Letters Patent N o. 698,484, dated April 29, 1902.

Application iiledNovemher 8', 1901. Serial No. 81,550. (No model.)V

To @ZZ whom, t may concern.:

Be it known that I, WILLIAM FoRsY'rH, a subject of the-Kingof Great Britain, residing at Belvidere, in the county of Boone and State of Illinois, have invented certain new and useful Improvements in Sewing Machines, of which the following is aspecification.

My invention relates to improvements in sewing-machines, and has particular relation to the provision of a gib-race which can be adj ustablyregulated to cooperate with the cross-head or cam of the needle-bar.

The objects of my invention are to provide a detachable gibrace which can be adjustably regulated.

A further object is to provide a gib which willcoperate with the race, and, further, to provide means for taking up the wear resulting from the reciprocating motion ofthe gib within the race.

To these and other ends said invention consists in the improved construction and combination of parts hereinafter fully described, illustratedin the accompanyingdrawings,and particularly set forth in the appended claims.

In the drawings, Figure l is an elevation of the face-plate of a sewing-machine, showing the needle-bar in position and omitting other parts which form no part of the invention. Fig. 2 is a sectional View taken on line 2 2 of Fig. 1. Fig. 3 is an enlarged plan View of the cross-head. Fig. 4 is an edge view of the same.` Fig. 5 is a detail of the gib-race. Fig. 6 is a detail of a modified form of gib connection with the cross-head.

In the provision of guides for the crossheads of the needle-bar, so far as I am aware, it has heretofore been the practice to provide a gibvoarried by the cross-head and adapted to cooperate with a fixed portion of the faceplate. By this construction there is the requirement of a careful forming of the parts primarily and afterward an accurate truing of the guide or the gib, or both.` Castings not perfectly made are therefore worthless, and hence there is an additional expense attached to the manufacture of this portion of the machine. 4In the present invention this requirement of a careful selection, &c., is eliminated to a great extent in thatthe gib-race is not only detachable, but its position can be regulated to correspond relatively to the proper position of the gibl on the cross-head, it being necessary only that the openings for the screws be tapped at the proper points. In the drawings I have presented a structure for accomplishing this result.

Referring thereto, 5 designates a face-plate of the usual form, guides for the gib, however, being omitted.

6 designates the needle-bar, and 7 the crosshead. Y The cross-head 7 is provided with the gib 8, either by its being formed integral therewith, as shown in Figs. l` to 4, or by being secured thereto, as shown in Fig. 6. In the latter constructioncams or cross-heads already in use can be utilized. As shown, the gib is preferably provided with means for taking up the wear, the means shown consisting in providing a slit 9, extending vertically therethrough, and an expanding-screw 10, operating therein, asbest shown in Fig. 4.

The gib-race 11 consists of a plate of suitable material, having a slot 12, which forms the raceway. Screw-holes 13 are provided at opposite ends, by means of which it may be secured to the face-plate. In securing the race in position the needle-bar, with the crosshead, is inserted, and its position is ascertained. The gib-race is also placed in position, after which the face-plate is tapped to receive the screws 14, which secure the race in its position. An oil-hole 15 is then tapped in the face-plate, which hole also serves to permit access to the expanding-screw 10 to take up wear. t

Inasmuch as the gib-race is detachable, it will be readily understood that its position relative to the cross-head can be regulated to a nicety without the requirement of a perfect face-plate. Furthermore, the face-plate is provided with a minimum number of openings, in addition to which the race can be readily oiled and the wear taken up without removal from the machine-head.

I do not limit myself to the precise details of construction, reserving the right to use modifications in so far as they may fall within the spirit and scope of the appended claims.

Having thus described my invention, what I claim as newist 1. In a sewing-machine, the combination with the needlebar; and the cross-head car- IOO ried thereby, said oross-head carrying a slitted adj'ustable gib; of a plate having a race for said gib detaohably carried by the faceplate, said race-plate having means preventing a movement of the gib laterally.

i 2. In a sewing-machine, the combination with the needle-bar; and the cross-head carried thereby, said cross-head carrying a slitted adjustable gib; of a plate having a race for said gib detachably carried by the faceplate, said plate having a slot of a length to pei-'mit lof the fnll longitudinal movement of the gib, whereby lateral movement of the gib will be prevented.

3. In a sewing-machine, the combination with a plate having a gibrace adapted to prevent lateral movement of the gib; of a Gross-head having a slittedgib movable 1ongitudinally of the race said gib having means constructed to expand the sides thereof for taking *up Wear.

I. In a sewing-machine, the combination with a plate having a gib race adapted to prevent lateral movement ol the gib; of a reoiprocating cross -head carrying a gib, said gib having a slit; and an adjusting-screw Carried by said gib and. adapted to expand the sides of said gib to take np Wear.

5. In a sewing-machine, a needle-bar; a cross-head carried thereby; a gib carried by the cross-head, saidgib being slitted longitudinally; an adjusting-screw carried by the gib and adapted to expand the sides of the gib; and a plate having a gib-race detachably carried by the face-plate, said race extending on opposite sides of the gib.

In Witness WhereofIhave hereunto set my hand in the presence of two Witnesses.

WILLIAM FORSYTI-I.

Witnesses:

LILLIAN I-IANLEY, CONRAD ALTHAUS. 

